Powers On, but no audio, and video is only greenish screen. This is from monitor out to yellow/red/white standard cable. Is there any more easy troubleshooting to try or does anyone here do repairs and/or conversions from Atari 800 to USB keyboard? If I can't get this thing fully working, I at least can use it as a keyboard for my MIST PC.

I have cool Atari stuff to trade in part or whole for someone's service too.

Please, please, please, don't wreck that nice piece of hardware by changing it into pretty useless PC keyboard... and if you do, offer at least the guts to someone who could use them There's a good chance of fixing the thing, as Atari used pretty cheap and low quality DRAMs that fail over the years. In your case, it could also be ROM, as the thing doesn't even get to memtest.What kind of equipment and knowledge do you have? If you can solder and have a decent logic probe, there's a chance you can fix it.

Hey Kubik, don't you worry. I have no intention of destroying an aging work of art! I can fix PCs and work with all OS's but older gear is new to me in the repair department. Havent soldered yet but have watched tutorial videos. I'm not spending a ton though on repairs. That's why I'm asking who here knows how to fix xl mobos?

If I turned this into a USB keyboard, the mobo would have to have NO CHANCE of repair and even then I'd get it in the hands of another "loving parent"...This is also a great board with socketed chips too. Nobody answered my prior question w. pics about two strange wires that look originated from a DIY job so I don't know next what to do.

If you're curious and love fixing stuff, this is a great way to start. I'd recommend you to get a good logic probe that can help you a lot. I am using thing called Superprobe that can also measure voltages, frequency, capacity etc. http://mondo-technology.com/super.htmlThen a decent soldering iron, and some other minor stuff. If the Atari will sacrifice its life to help you get some repair skills, it will be worth it I can offer a helping hand, but you'd need to ship the board over to Germany.If you're going to try it yourself, feel free to ask for advices.I am not sure about those two wires you're mentioning, any pictures or details what are they connected to?

I see, I did not notice your previous post, sorry. I can't say from top of my head what the wires are good to. They still could be installed from the factory, those things were happening often in 80's - like that famous transistor glued to the top of CPU in some issues of ZX Spectrum, or the blitter fix for Atari Mega I should have two 800XL sitting in my cellar and waiting for inspection and repair. I can't give you any schedule, but I'll prioritize the task. I've spent two weeks getting my Amstrads (CPC and PCW) up and running, so it's a good time for a change and do some Atari stuff again, and I can check the wires, or what they might be good for.As for the superprobe - I am not sure if they're for sale, but I am thinking about designing a PCB for it, I am sure more people would be interested.